What is Epimerization?

What is Epimerization?

Epimerization is a process in stereochemistry in which there is a change in the configuration of only one chiral center. As a result, a diastereomer is formed. The classical example of this in medicine is tetracycline.

What are Epimeric sugars?

Epimers are carbohydrates which vary in one position for the placement of the -OH group. The best examples are for D-glucose and D-galactose. That single different makes D-glucose and D-galactose epimers. They are not enantiomers, or diastereomers, or isomers, they are only epimers.

What does Epimeric mean in chemistry?

Illustrated Glossary of Organic Chemistry – Epimer. Epimer: One of a pair of stereoisomers that differ in the absolute configuration of a single stereocenter. When the molecule has only one stereocenter then the epimers are enantiomers. When the molecule has two or more stereocenters then the epimers are diastereomers.

What is difference between racemization and epimerization?

The key difference between epimerization and racemization is that epimerization involves the conversion of an epimer into its chiral counterpart whereas racemization is a conversion of an optically active species into an optically inactive species. Epimerization and racemization are chemical conversions.

Is Epimerization reversible?

(1−4) A wide range of reactions have been developed to transform C(sp3)–H bonds into different functional groups. Racemization or epimerization via reversible cleavage of C(sp3)–H bonds might offer an invaluable tool for editing the stereochemistry of organic compounds.

How can you prevent racemization?

Adding HOBt, 6-Cl-HOBt or HOAt suppresses the racemization. Histidine and cysteine are especially prone to racemization. Protecting the pi imidazole nitrogen in the histidine side-chain with the methoxybenzyl group greatly reduces racemization.

What is Racemisation with example?

When a racemic mixture is obtained by mixing a chemical then it is called chemical racemisation. For example, 2-butyl phenyl ketone gives a racemic mixture on adding an acid.